The MBTI was constructed by Katharine Cook Briggs and her daughter Isabel Briggs Myers. It is based on the conceptual theory proposed by Carl Jung,[4] who had speculated that humans experience the world using four principal psychological functions – sensation, intuition, feeling, and thinking – and that one of these four functions is dominant for a person most of the time.[5]

The MBTI was constructed for normal populations and emphasizes the value of naturally occurring differences.[6] "The underlying assumption of the MBTI is that we all have specific preferences in the way we construe our experiences, and these preferences underlie our interests, needs, values, and motivation."[7]

Although popular in the business sector, the MBTI exhibits significant psychometric deficiencies, notably including poor validity (i.e. not measuring what it purports to measure or having predictive power), poor reliability (giving different results for the same person on different occasions), measuring categories that are not independent (some dichotomous traits have been noted to correlate with each other), and not being comprehensive (due to missing neuroticism).[8][9][10][11] The four scales used in the MBTI have some correlation with four of the Big Five personality traits, which are a more commonly accepted framework.[12]

Katharine Cook Briggs began her research into personality in 1917. Upon meeting her future son-in-law, she observed marked differences between his personality and that of other family members. Briggs embarked on a project of reading biographies, and subsequently developed a typology wherein she proposed four temperaments: meditative (or thoughtful), spontaneous, executive, and social.[13][14]

After the English translation of Jung's book Psychological Types was published in 1923 (first published in German in 1921), she recognized that Jung's theory was similar to, but went far beyond, her own.[1]:22 Briggs's four types were later identified as corresponding to the IXXXs, EXXPs, EXTJs and EXFJs.[clarification needed][13][14] Her first publications were two articles describing Jung's theory, in the journal New Republic in 1926 ("Meet Yourself Using the Personality Paint Box") and 1928 ("Up From Barbarism"). After extensively studying the work of Jung, they turned their interest in human behavior into efforts to turn the theory of psychological types to practical use.[2][13]

Briggs's daughter, Isabel Briggs Myers, added to her mother's typological research, which she would progressively take over entirely. Myers graduated first in her class from Swarthmore College in 1919[1]:xx and wrote a mystery novel, Murder Yet to Come, in 1929 using typological ideas (which won the National Detective Murder Mystery Contest that year). However, neither Myers nor Briggs was formally educated in the discipline of psychology, and both were self-taught in the field of psychometric testing.[1]:xiii Myers therefore apprenticed herself to Edward N. Hay, who was then personnel manager for a large Philadelphia bank and who went on to start one of the first successful personnel consulting firms in the United States. From Hay, Myers learned rudimentary test construction, scoring, validation, and statistical methods.[1]:xiii, xx

Briggs and Myers began creating the indicator during World War II[2] in the belief that a knowledge of personality preferences would help women who were entering the industrial workforce for the first time to identify the sort of war-time jobs that would be "most comfortable and effective" for them.[1]:xiii The Briggs Myers Type Indicator Handbook was published in 1944. The indicator changed its name to "Myers–Briggs Type Indicator" in 1956.[15] Myers' work attracted the attention of Henry Chauncey, head of the Educational Testing Service. Under these auspices, the first MBTI Manual was published in 1962. The MBTI received further support from Donald W. MacKinnon, head of the Institute of Personality and Social Research at the University of California, Berkeley; W. Harold Grant, a professor at Michigan State University and Auburn University; and Mary H. McCaulley of the University of Florida. The publication of the MBTI was transferred to Consulting Psychologists Press in 1975, and the Center for Applications of Psychological Type was founded as a research laboratory.[1]:xxi

After Myers' death in May 1980, Mary McCaulley updated the MBTI Manual and the second edition was published in 1985.[16] The third edition appeared in 1998.

Jung's theory of psychological types was not based on controlled scientific studies,[17] but instead on clinical observation, introspection, and anecdote—methods regarded as inconclusive in the modern field of scientific psychology.[17]

Jung's typology theories postulated a sequence of four cognitive functions (thinking, feeling, sensation, and intuition), each having one of two polar orientations (extraversion or introversion), giving a total of eight dominant functions. The MBTI is based on these eight hypothetical functions, although with some differences in expression from Jung's model (see Differences from Jung below). While the Jungian model offers empirical evidence for the first three dichotomies, whether the Briggs had evidence for the J-P preference is unclear.[verification needed]

The MBTI takes what is called a "structured" approach to personality assessment. The responses to items are considered "closed" and interpreted according to the theory of the test constructers in scoring. This is contrary to the "projective" approach to personality assessment advocated by psychodynamic theorists such as Carl Jung. Indeed, Jung was a proponent of the "word association" test as a measure of the unconscious dispositions influencing behavior. This approach uses "open-ended" responses that need to be interpreted in the context of the "whole" person, and not according to the preconceived theory of the test constructers. Supporters of the projective approach to personality assessment are critical of the structured approach because defense mechanisms may distort responses to the closed items on structured tests.

The most notable addition of Myers and Briggs ideas to Jung's original thought is their concept that a given type's fourth letter (J or P) indicates a person's preferred extraverted function, which is the dominant function for extraverted types and the auxiliary function for introverted types.[1]:21–22

Jung theorized that the dominant function acts alone in its preferred world: exterior for extraverts and interior for introverts. The remaining three functions, he suggested, operate together in the opposite orientation. If the dominant cognitive function is introverted the other functions are extraverted and vice versa. The MBTI Manual summarizes references in Jung's work to the balance in psychological type as follows: "There are several references in Jung's writing to the three remaining functions having an opposite attitudinal character. For example, in writing about introverts with thinking dominant ... Jung commented that the counterbalancing functions have an extraverted character."[16] However, many MBTI practitioners hold that the tertiary function is oriented in the same direction as the dominant function.[18] Using the INTP type as an example, the orientation would be as follows:

The MBTI Manual states that the indicator "is designed to implement a theory; therefore, the theory must be understood to understand the MBTI".[19]:1 Fundamental to the MBTI is the theory of psychological type as originally developed by Carl Jung.[1]:xiii Jung proposed the existence of two dichotomous pairs of cognitive functions:

The "rational" (judging) functions: thinking and feeling

The "irrational" (perceiving) functions: sensation and intuition

Jung believed that for every person, each of the functions is expressed primarily in either an introverted or extraverted form.[1]:17 Based on Jung's original concepts, Briggs and Myers developed their own theory of psychological type, described below, on which the MBTI is based. However, although psychologist Hans Eysenck called the MBTI a moderately successful quantification of Jung's original principles as outlined in Psychological Types,[20] he also said, "[The MBTI] creates 16 personality types which are said to be similar to Jung's theoretical concepts. I have always found difficulties with this identification, which omits one half of Jung's theory (he had 32 types, by asserting that for every conscious combination of traits there was an opposite unconscious one). Obviously, the latter half of his theory does not admit of questionnaire measurement, but to leave it out and pretend that the scales measure Jungian concepts is hardly fair to Jung."[21] In any event, both models remain hypothetical, with no controlled scientific studies supporting either Jung's original concept of type or the Myers–Briggs variation.[17]

Jung's typological model regards psychological type as similar to left or right handedness: people are either born with, or develop, certain preferred ways of perceiving and deciding. The MBTI sorts some of these psychological differences into four opposite pairs, or "dichotomies", with a resulting 16 possible psychological types. None of these types is "better" or "worse"; however, Briggs and Myers theorized that people innately "prefer" one overall combination of type differences.[1]:9 In the same way that writing with the left hand is difficult for a right-hander, so people tend to find using their opposite psychological preferences more difficult, though they can become more proficient (and therefore behaviorally flexible) with practice and development.

The 16 types are typically referred to by an abbreviation of four letters—the initial letters of each of their four type preferences (except in the case of intuition, which uses the abbreviation "N" to distinguish it from introversion). For instance:

The four pairs of preferences or "dichotomies" are shown in the adjacent table.

The terms used for each dichotomy have specific technical meanings relating to the MBTI, which differ from their everyday usage. For example, people who prefer judgment over perception are not necessarily more "judgmental" or less "perceptive", nor does the MBTI instrument measure aptitude; it simply indicates for one preference over another.[19]:3 Someone reporting a high score for extraversion over introversion cannot be correctly described as more extraverted: they simply have a clear preference.

Point scores on each of the dichotomies can vary considerably from person to person, even among those with the same type. However, Isabel Myers considered the direction of the preference (for example, E vs. I) to be more important than the degree of the preference (for example, very clear vs. slight).[16] The expression of a person's psychological type is more than the sum of the four individual preferences. The preferences interact through type dynamics and type development.

Myers–Briggs literature uses the terms extraversion and introversion as Jung first used them. Extraversion means literally outward-turning and introversion, inward-turning.[22] These specific definitions differ somewhat from the popular usage of the words. Extraversion is the spelling used in MBTI publications.

The preferences for extraversion and introversion are often called "attitudes". Briggs and Myers recognized that each of the cognitive functions can operate in the external world of behavior, action, people, and things ("extraverted attitude") or the internal world of ideas and reflection ("introverted attitude"). The MBTI assessment sorts for an overall preference for one or the other.

People who prefer extraversion draw energy from action: they tend to act, then reflect, then act further. If they are inactive, their motivation tends to decline. To rebuild their energy, extraverts need breaks from time spent in reflection. Conversely, those who prefer introversion "expend" energy through action: they prefer to reflect, then act, then reflect again. To rebuild their energy, introverts need quiet time alone, away from activity.[23]

An extravert's flow is directed outward toward people and objects, whereas the introvert's is directed inward toward concepts and ideas. Contrasting characteristics between extraverted and introverted people include:

Extraverted are action-oriented, while introverted are thought-oriented.

Extraverted seek breadth of knowledge and influence, while introverted seek depth of knowledge and influence.

Extraverted often prefer more frequent interaction, while introverted prefer more substantial interaction.

Extraverted recharge and get their energy from spending time with people, while introverted recharge and get their energy from spending time alone; they consume their energy through the opposite process.[24]

Two perceiving functions: sensation (usually called sensing in MBTI writings) and intuition

Two judging functions: thinking and feeling

According to Jung's typology model, each person uses one of these four functions more dominantly and proficiently than the other three; however, all four functions are used at different times depending on the circumstances.

Sensing and intuition are the information-gathering (perceiving) functions. They describe how new information is understood and interpreted. People who prefer sensing are more likely to trust information that is in the present, tangible, and concrete: that is, information that can be understood by the five senses. They tend to distrust hunches, which seem to come "out of nowhere".[1]:2 They prefer to look for details and facts. For them, the meaning is in the data. On the other hand, those who prefer intuition tend to trust information that is less dependent upon the senses, that can be associated with other information (either remembered or discovered by seeking a wider context or pattern). They may be more interested in future possibilities. For them, the meaning is in the underlying theory and principles which are manifested in the data.

Thinking and feeling are the decision-making (judging) functions. The thinking and feeling functions are both used to make rational decisions, based on the data received from their information-gathering functions (sensing or intuition). Those who prefer thinking tend to decide things from a more detached standpoint, measuring the decision by what seems reasonable, logical, causal, consistent, and matching a given set of rules. Those who prefer feeling tend to come to decisions by associating or empathizing with the situation, looking at it 'from the inside' and weighing the situation to achieve, on balance, the greatest harmony, consensus and fit, considering the needs of the people involved. Thinkers usually have trouble interacting with people who are inconsistent or illogical, and tend to give very direct feedback to others. They are concerned with the truth and view it as more important.

As noted already, people who prefer thinking do not necessarily, in the everyday sense, "think better" than their feeling counterparts, in the common sense; the opposite preference is considered an equally rational way of coming to decisions (and, in any case, the MBTI assessment is a measure of preference, not ability). Similarly, those who prefer feeling do not necessarily have "better" emotional reactions than their thinking counterparts. In many cases, however, people who use thinking functions as either dominant or auxiliary tend to have more underdeveloped feeling functions, and often have more trouble with regulating and making healthy and productive decisions based on their feelings.

A diagram depicting the cognitive functions of each type: A type's background color represents its dominant function and its text color represents its auxiliary function.

According to Jung, people use all four cognitive functions. However, one function is generally used in a more conscious and confident way. This dominant function is supported by the secondary (auxiliary) function, and to a lesser degree the tertiary function. The fourth and least conscious function is always the opposite of the dominant function. Myers called this inferior function the "shadow".[1]:84

The four functions operate in conjunction with the attitudes (extraversion and introversion). Each function is used in either an extraverted or introverted way. A person whose dominant function is extraverted intuition, for example, uses intuition very differently from someone whose dominant function is introverted intuition.

Myers and Briggs added another dimension to Jung's typological model by identifying that people also have a preference for using either the judging function (thinking or feeling) or their perceiving function (sensing or intuition) when relating to the outside world (extraversion).

Myers and Briggs held that types with a preference for judging show the world their preferred judging function (thinking or feeling). So, TJ types tend to appear to the world as logical and FJ types as empathetic. According to Myers,[1]:75 judging types like to "have matters settled".

Those types who prefer perception show the world their preferred perceiving function (sensing or intuition). So, SP types tend to appear to the world as concrete and NP types as abstract. According to Myers,[1]:75 perceptive types prefer to "keep decisions open".

For extraverts, the J or P indicates their dominant function; for introverts, the J or P indicates their auxiliary function[citation needed]. Introverts tend to show their dominant function outwardly only in matters "important to their inner worlds".[1]:13 For example:

Because the ENTJ type is extraverted, the J indicates that the dominant function is the preferred judging function (extraverted thinking). The ENTJ type introverts the auxiliary perceiving function (introverted intuition). The tertiary function is sensing and the inferior function is introverted feeling.

Because the INTJ type is introverted, however, the J instead indicates that the auxiliary function is the preferred judging function (extraverted thinking). The INTJ type introverts the dominant perceiving function (introverted intuition). The tertiary function is feeling and the inferior function is extraverted sensing.

The current North American English version of the MBTI Step I includes 93 forced-choice questions (88 are in the European English version). "Forced-choice" means that a person has to choose only one of two possible answers to each question. The choices are a mixture of word pairs and short statements. Choices are not literal opposites, but chosen to reflect opposite preferences on the same dichotomy. Participants may skip questions if they feel they are unable to choose.

Using psychometric techniques, such as item response theory, the MBTI will then be scored and will attempt to identify the preference, and clarity of preference, in each dichotomy. After taking the MBTI, participants are usually asked to complete a "Best Fit" exercise (see below) and then given a readout of their Reported Type, which will usually include a bar graph and number (Preference Clarity Index) to show how clear they were about each preference when they completed the questionnaire.

During the early development of the MBTI, thousands of items were used. Most were eventually discarded because they did not have high "midpoint discrimination", meaning the results of that one item did not, on average, move an individual score away from the midpoint. Using only items with high midpoint discrimination allows the MBTI to have fewer items on it, but still provide as much statistical information as other instruments with many more items with lower midpoint discrimination.

Isabel Myers had noted that people of any given type shared differences, as well as similarities. At the time of her death, she was developing a more in-depth method of measuring how people express and experience their individual type pattern.

In 1987, an advanced scoring system was developed for the MBTI. From this was developed the Type Differentiation Indicator (Saunders, 1989) which is a scoring system for the longer MBTI, Form J,[25] which includes the 290 items written by Myers that had survived her previous item analyses. It yields 20 subscales (five under each of the four dichotomous preference scales), plus seven additional subscales for a new "Comfort-Discomfort" factor (which purportedly corresponds to the missing factor of neuroticism).

Also included is a composite of these called "strain". There are also scales for type-scale consistency and comfort-scale consistency. Reliability of 23 of the 27 TDI subscales is greater than 0.50, "an acceptable result given the brevity of the subscales" (Saunders, 1989).

In 1989, a scoring system was developed for only the 20 subscales for the original four dichotomies. This was initially known as "Form K" or the "Expanded Analysis Report". This tool is now called the "MBTI Step II".

Form J or the TDI included the items (derived from Myers' and McCaulley's earlier work) necessary to score what became known as "Step III".[27] (The 1998 MBTI Manual reported that the two instruments were one and the same[28]) It was developed in a joint project involving the following organizations: CPP, the publisher of the whole family of MBTI works; CAPT (Center for Applications of Psychological Type), which holds all of Myers' and McCaulley's original work; and the MBTI Trust, headed by Katharine and Peter Myers. Step III was advertised as addressing type development and the use of perception and judgment by respondents.[29]

The MBTI has been successfully translated and adapted into over 20 languages,[30][31] including reviews by subject-matter experts fluent in the native language, and statistical analysis to check that the questions still measure the same psychological concepts as the original US English questionnaire.[32]

These precepts are generally used in the ethical administration of the MBTI:

Type not trait

The MBTI sorts for type; it does not indicate the strength of ability. It allows the clarity of a preference to be ascertained (Bill clearly prefers introversion), but not the strength of preference (Jane strongly prefers extraversion) or degree of aptitude (Harry is good at thinking). In this sense, it differs from trait-based tools such as 16PF. Type preferences are polar opposites: a precept of MBTI is that people fundamentally prefer one thing over the other, not a bit of both.

Own best judge

People are considered the best judge of their own type. While the MBTI provides a Reported Type, this is considered only an indication of their probable overall Type. A Best Fit Process is usually used to allow respondents to develop their understanding of the four dichotomies, to form their own hypothesis as to their overall Type, and to compare this against the Reported Type. In more than 20% of cases, the hypothesis and the Reported Type differ in one or more dichotomies. Using the clarity of each preference, any potential for bias in the report, and often, a comparison of two or more whole Types may then help respondents determine their own Best Fit.

No right or wrong

No preference or total type is considered better or worse than another. They are all 'Gifts Differing', as emphasized by the title of Isabel Briggs Myers' book on this subject.

Voluntary

Compelling anyone to take the MBTI is considered unethical. It should always be taken voluntarily.[33]

Confidentiality

The result of the MBTI Reported and Best Fit type are confidential between the individual and administrator, and ethically, not for disclosure without permission.

Not for selection

The results of the assessment should not be used to "label, evaluate, or limit the respondent in any way" (emphasis original).[33] Since all types are valuable, and the MBTI measures preferences rather than aptitude, the MBTI is not considered a proper instrument for purposes of employment selection. Many professions contain highly competent individuals of different types with complementary preferences.

Importance of proper feedback

People should always be given detailed feedback from a trained administrator and an opportunity to undertake a Best Fit exercise to check against their Reported Type. This feedback can be given in person, by telephone or electronically.

Estimated percentages of the 16 types in the United States population.[34]

The interaction of two, three, or four preferences is known as "type dynamics". Although type dynamics has received little or no empirical support to substantiate its viability as a scientific theory,[35] Myers and Briggs asserted that for each of the 16 four-preference types, one function is the most dominant and is likely to be evident earliest in life. A secondary or auxiliary function typically becomes more evident (differentiated) during teenaged years and provides balance to the dominant. In normal development, individuals tend to become more fluent with a third, tertiary function during mid-life, while the fourth, inferior function remains least consciously developed. The inferior function is often considered to be more associated with the unconscious, being most evident in situations such as high stress (sometimes referred to as being "in the grip" of the inferior function).

However, the use of type dynamics is disputed: in the conclusion of various studies on the subject of type dynamics, James H. Reynierse writes, "Type dynamics has persistent logical problems and is fundamentally based on a series of category mistakes; it provides, at best, a limited and incomplete account of type related phenomena"; and "type dynamics relies on anecdotal evidence, fails most efficacy tests, and does not fit the empirical facts". His studies gave the clear result that the descriptions and workings of type dynamics do not fit the real behavior of people. He suggests getting completely rid of type dynamics, because it does not help, but hinders understanding of personality. The presumed order of functions 1 to 4 did only occur in one out of 540 test results.[36]

The sequence of differentiation of dominant, auxiliary, and tertiary functions through life is termed type development. This is an idealized sequence that may be disrupted by major life events.

The dynamic sequence of functions and their attitudes can be determined in the following way:

The overall lifestyle preference (J-P) determines whether the judging (T-F) or perceiving (S-N) preference is most evident in the outside world; i.e., which function has an extraverted attitude

The attitude preference (E-I) determines whether the extraverted function is dominant or auxiliary

For those with an overall preference for extraversion, the function with the extraverted attitude will be the dominant function. For example, for an ESTJ type the dominant function is the judging function, thinking, and this is experienced with an extraverted attitude. This is notated as a dominant Te. For an ESTP, the dominant function is the perceiving function, sensing, notated as a dominant Se.

The auxiliary function for extraverts is the secondary preference of the judging or perceiving functions, and it is experienced with an introverted attitude: for example, the auxiliary function for ESTJ is introverted sensing (Si) and the auxiliary for ESTP is introverted thinking (Ti).

For those with an overall preference for introversion, the function with the extraverted attitude is the auxiliary; the dominant is the other function in the main four letter preference. So the dominant function for ISTJ is introverted sensing (Si) with the auxiliary (supporting) function being extraverted thinking (Te).

The tertiary function is the opposite preference from the auxiliary. For example, if the Auxiliary is thinking then the Tertiary would be feeling. The attitude of the tertiary is the subject of some debate and therefore is not normally indicated; i.e. if the auxiliary was Te then the tertiary would be F (not Fe or Fi)

The inferior function is the opposite preference and attitude from the Dominant, so for an ESTJ with dominant Te the inferior would be Fi.

Note that for extraverts, the dominant function is the one most evident in the external world. For introverts, however, it is the auxiliary function that is most evident externally, as their dominant function relates to the interior world.

Some examples of whole types may clarify this further. Taking the ESTJ example above:

Extraverted function is a judging function (T-F) because of the overall J preference

Inferior function is the opposite of the Dominant: introverted feeling (Fi)

The dynamics of the ESTJ are found in the primary combination of extraverted thinking as their dominant function and introverted sensing as their auxiliary function: the dominant tendency of ESTJs to order their environment, to set clear boundaries, to clarify roles and timetables, and to direct the activities around them is supported by their facility for using past experience in an ordered and systematic way to help organize themselves and others. For instance, ESTJs may enjoy planning trips for groups of people to achieve some goal or to perform some culturally uplifting function. Because of their ease in directing others and their facility in managing their own time, they engage all the resources at their disposal to achieve their goals. However, under prolonged stress or sudden trauma, ESTJs may overuse their extraverted thinking function and fall into the grip of their inferior function, introverted feeling. Although the ESTJ can seem insensitive to the feelings of others in their normal activities, under tremendous stress, they can suddenly express feelings of being unappreciated or wounded by insensitivity.

Looking at the diametrically opposite four-letter type, INFP:

Extraverted function is a perceiving function (S-N) because of the P preference

Introverted function is dominant because of the I preference

Dominant function is therefore introverted feeling (Fi)

Auxiliary function is extraverted intuition (Ne)

Tertiary function is the opposite of the Auxiliary: sensing (S)

Inferior function is the opposite of the Dominant: extraverted thinking (Te)

The dynamics of the INFP rest on the fundamental correspondence of introverted feeling and extraverted intuition. The dominant tendency of the INFP is toward building a rich internal framework of values and toward championing human rights. They often devote themselves behind the scenes to causes such as civil rights or saving the environment. Since they tend to avoid the limelight, postpone decisions, and maintain a reserved posture, they are rarely found in executive-director-type positions of the organizations that serve those causes. Normally, the INFP dislikes being "in charge" of things. When not under stress, the INFP radiates a pleasant and sympathetic demeanor, but under extreme stress, they can suddenly become rigid and directive, exerting their extraverted thinking erratically.

Every type, and its opposite, is the expression of these interactions, which give each type its unique, recognizable signature.

The test is scored by evaluating each answer in terms of what it reveals about the taker. Each question is relevant to one of the following cognitive learning styles. Each is not a polar opposite, but a gradual continuum.

The extraverted types learn best by talking and interacting with others. By interacting with the physical world, extraverts can process and make sense of new information. The introverted types prefer quiet reflection and privacy. Information processing occurs for introverts as they explore ideas and concepts internally.

The second continuum reflects what people focus their attentions on. Sensing types enjoy a learning environment in which the material is presented in a detailed and sequential manner. Sensing types often attend to what is occurring in the present, and can move to the abstract after they have established a concrete experience. Intuitive types prefer a learning atmosphere in which an emphasis is placed on meaning and associations. Insight is valued higher than careful observation, and pattern recognition occurs naturally for intuitive types.

The third continuum reflects a person's decision preferences. Thinking types desire objective truth and logical principles and are natural at deductive reasoning. Feeling types place an emphasis on issues and causes that can be personalized while they consider other people's motives.

The fourth continuum reflects how a person regards complexity. Judging types will thrive when information is organized and structured, and they will be motivated to complete assignments in order to gain closure. Perceiving types will flourish in a flexible learning environment in which they are stimulated by new and exciting ideas. Judging types like to be on time, while perceiving types may be late and/or procrastinate.

David W. Keirsey mapped four "temperaments" to the existing Myers–Briggs system groupings: SP, SJ, NF and NT; this often results in confusion of the two theories. However, the Keirsey Temperament Sorter is not directly associated with the official Myers–Briggs Type Indicator.[citation needed]

McCrae and Costa based their Five Factor Model (FFM) on Goldberg's Big Five theory.[37] McCrae and Costa[38] present correlations between the MBTI scales and the currently popular Big Five personality constructs measured, for example, by the NEO-PI-R.[39] The five purported personality constructs have been labeled: extraversion, openness, agreeableness, conscientiousness, and neuroticism (emotional instability), although there is not universal agreement on the Big Five theory and the related Five-Factor Model (FFM).[40][41] The following study is based on the results from 267 men followed as part of a longitudinal study of aging. (Similar results were obtained with 201 women.)

The closer the number is to 1.0 or −1.0, the higher the degree of correlation.

These results suggest that the four MBTI scales can be incorporated within the Big Five personality trait constructs, but that the MBTI lacks a measure for emotional stability dimension of the Big Five (though the TDI, discussed above, has addressed that dimension). Emotional stability (or neuroticism) is a predictor of depression and anxiety disorders. These correlations refer to the second letter shown, i.e., the table shows that I and P have negative correlations with extraversion and conscientiousness, respectively, while F and N have positive correlations with agreeableness and openness, respectively.

These findings led McCrae and Costa to conclude that, "correlational analyses showed that the four MBTI indices did measure aspects of four of the five major dimensions of normal personality. The five-factor model provides an alternative basis for interpreting MBTI findings within a broader, more commonly shared conceptual framework." However, "there was no support for the view that the MBTI measures truly dichotomous preferences or qualitatively distinct types, instead, the instrument measures four relatively independent dimensions."[38]

It has been estimated that between a third and a half of the published material on the MBTI has been produced for the special conferences of the Center for the Application of Psychological Type (which provide the training in the MBTI, and are funded by sales of the MBTI) or as papers in the Journal of Psychological Type (which is edited and supported by Myers–Briggs advocates and by sales of the indicator).[43] It has been argued that this reflects a lack of critical scrutiny.[43] Many of the studies that endorse MBTI are methodologically weak or unscientific.[10] A 1996 review by Gardner and Martinko concluded: "It is clear that efforts to detect simplistic linkages between type preferences and managerial effectiveness have been disappointing. Indeed, given the mixed quality of research and the inconsistent findings, no definitive conclusion regarding these relationships can be drawn."[10][44]

As described in the § Four dichotomies section, Isabel Myers considered the direction of the preference (for example, E vs. I) to be more important than the degree of the preference. Statistically, this would mean that scores on each MBTI scale would show a bimodal distribution with most people scoring near the ends of the scales, thus dividing people into either, e.g., an extroverted or an introverted psychological type. However, most studies have found that scores on the individual scales were actually distributed in a centrally peaked manner, similar to a normal distribution, indicating that the majority of people were actually in the middle of the scale and were thus neither clearly introverted nor extroverted. Most personality traits do show a normal distribution of scores from low to high, with about 15% of people at the low end, about 15% at the high end and the majority of people in the middle ranges. But in order for the MBTI to be scored, a cut-off line is used at the middle of each scale and all those scoring below the line are classified as a low type and those scoring above the line are given the opposite type. Thus, psychometric assessment research fails to support the concept of type, but rather shows that most people lie near the middle of a continuous curve.[9][38][46][47][48] "Although we do not conclude that the absence of bimodality necessarily proves that the MBTI developers' theory-based assumption of categorical "types" of personality is invalid, the absence of empirical bimodality in IRT-based research of MBTI scores does indeed remove a potentially powerful line of evidence that was previously available to "type" advocates to cite in defense of their position."[48]

The content of the MBTI scales is problematic. In 1991, a National Academy of Sciences committee reviewed data from MBTI research studies and concluded that only the I-E scale has high correlations with comparable scales of other instruments and low correlations with instruments designed to assess different concepts, showing strong validity. In contrast, the S-N and T-F scales show relatively weak validity. The 1991 review committee concluded at the time there was "not sufficient, well-designed research to justify the use of the MBTI in career counseling programs".[49] This study based its measurement of validity on "criterion-related validity (i.e., does the MBTI predict specific outcomes related to interpersonal relations or career success/job performance?)."[49] There is insufficient evidence to make claims about utility, particularly of the four letter type derived from a person's responses to the MBTI items.[9]

The accuracy of the MBTI depends on honest self-reporting.[19]:52–53 Unlike some personality questionnaires, such as the 16PF Questionnaire, the Minnesota Multiphasic Personality Inventory, or the Personality Assessment Inventory, the MBTI does not use validity scales to assess exaggerated or socially desirable responses.[11] As a result, individuals motivated to do so can fake their responses,[50] and one study found that the MBTI judgment/perception dimension correlates weakly with the Eysenck Personality Questionnaire lie scale.[51] If respondents "fear they have something to lose, they may answer as they assume they should."[19]:53 However, the MBTI ethical guidelines state, "It is unethical and in many cases illegal to require job applicants to take the Indicator if the results will be used to screen out applicants."[33] The intent of the MBTI is to provide "a framework for understanding individual differences, and ... a dynamic model of individual development".[52]

The terminology of the MBTI has been criticized as being very "vague and general",[53] so as to allow any kind of behavior to fit any personality type, which may result in the Forer effect, where people give a high rating to a positive description that supposedly applies specifically to them.[9][17] Others argue that while the MBTI type descriptions are brief, they are also distinctive and precise.[54]:14–15 Some theorists, such as David Keirsey, have expanded on the MBTI descriptions, providing even greater detail. For instance, Keirsey's descriptions of his four temperaments, which he correlated with the sixteen MBTI personality types, show how the temperaments differ in terms of language use, intellectual orientation, educational and vocational interests, social orientation, self-image, personal values, social roles, and characteristic hand gestures.[54]:32–207

Researchers have reported that the JP and the SN scales correlate with one another.[38] One factor-analytic study based on (N=1291) college-aged students found six different factors instead of the four purported dimensions, thereby raising doubts as to the construct validity of the MBTI.[55]

According to Hans Eysenck: "The main dimension in the MBTI is called E-I, or extraversion-introversion; this is mostly a sociability scale, correlating quite well with the MMPI social introversion scale (negatively) and the Eysenck Extraversion scale (positively).[56] Unfortunately, the scale also has a loading on neuroticism, which correlates with the introverted end. Thus introversion correlates roughly (i.e. averaging values for males and females) -.44 with dominance, -.24 with aggression, +.37 with abasement, +.46 with counselling readiness, -.52 with self-confidence, -.36 with personal adjustment, and -.45 with empathy. The failure of the scale to disentangle Introversion and Neuroticism (there is no scale for neurotic and other psychopathological attributes in the MBTI) is its worst feature, only equalled by the failure to use factor analysis in order to test the arrangement of items in the scale."[20]

The test-retest reliability of the MBTI tends to be low. Large numbers of people (between 39% and 76% of respondents) obtain different type classifications when retaking the indicator after only five weeks.[9][47][57] In Fortune Magazine (May 15, 2013), an article titled "Have we all been duped by the Myers-Briggs Test" stated:

“

The interesting – and somewhat alarming – fact about the MBTI is that, despite its popularity, it has been subject to sustained criticism by professional psychologists for over three decades. One problem is that it displays what statisticians call low "test-retest reliability." So if you retake the test after only a five-week gap, there's around a 50% chance that you will fall into a different personality category compared to the first time you took the test.

A second criticism is that the MBTI mistakenly assumes that personality falls into mutually exclusive categories. ... The consequence is that the scores of two people labelled "introverted" and "extroverted" may be almost exactly the same, but they could be placed into different categories since they fall on either side of an imaginary dividing line.[58]

”

Within each dichotomy scale, as measured on Form G, about 83% of categorizations remain the same when people are retested within nine months and around 75% when retested after nine months. About 50% of people re-administered the MBTI within nine months remain the same overall type and 36% the same type after more than nine months.[59] For Form M (the most current form of the MBTI instrument), the MBTI Manual reports that these scores are higher (p. 163, Table 8.6).

In one study, when people were asked to compare their preferred type to that assigned by the MBTI assessment, only half of people chose the same profile.[60]

It has been argued that criticisms regarding the MBTI mostly come down to questions regarding the validity of its origins, not questions regarding the validity of the MBTI's usefulness.[61] Others argue that the MBTI can be a reliable measurement of personality; it just so happens that "like all measures, the MBTI yields scores that are dependent on sample characteristics and testing conditions".[62]

Isabel Myers claimed that the proportion of different personality types varied by choice of career or course of study.[1]:40–51[16] However, researchers examining the proportions of each type within varying professions report that the proportion of MBTI types within each occupation is close to that within a random sample of the population.[9] Some researchers have expressed reservations about the relevance of type to job satisfaction, as well as concerns about the potential misuse of the instrument in labeling people.[9][63]

CPP became the exclusive publisher of the MBTI in 1975. They call it "the world's most widely used personality assessment", with as many as two million assessments administered annually.[64] CPP and other proponents state that the indicator meets or exceeds the reliability of other psychological instruments and cite reports of individual behavior.[65][47][66][excessive citations]

Although meta-analysis claim support for validity and reliability,[67][68] studies suggest that the MBTI "lacks convincing validity data" and that it is pseudoscience.[9][38][46][47][69][70]

The MBTI is not a useful predictor of job performance.[9][49][71] As noted above under Precepts and ethics, the MBTI measures preferences, not ability. The use of the MBTI as a predictor of job success is expressly discouraged in the Manual.[19]:78 However, the MBTI continues to be popular because many people lack psychometric sophistication, it is not difficult to understand, and there are many supporting books, websites and other sources which are readily available to the general public.[72]

^Dawes, Robyn (2004). "Time for a critical empirical investigation of the MBTI: Case and Phillipson are right to highlight the pre-scientific roots of the MBTI, but they fail to separate the issue of the validity or usefulness of the MBTI from the issue of the validity of its origins.(Myers-Briggs Type Indicator)". European Business Forum (18).